Switching power converters are widely used for high power applications because of their high efficiency and small size. Converter efficiency is increasingly important at low and medium power levels. For example, buck converters are particularly well suited for providing high current at low voltages required by state of the art high performance integrated circuits such as microprocessors, graphics processors, and network processors. In general, buck converters are typically implemented with active components such as a pulse width modulation controller (PWM), driver, power MOSFETs (metal oxide semiconductor field effect transistors), and passive components such as inductors, transformers or coupled inductors, capacitors, and resistors.
Most conventional buck converters use direct drive for switching on the MOSFETs of the power stage. The energy used for the gate drive process is then typically dissipated. Some conventional approaches attempt to recover part of the gate drive energy by storing the energy in external capacitors, which increases the complexity of the driver because an additional pin and external components are required. The storage capacitance instead can be integrated within the driver, but doing so increases the size and cost of the driver circuit.